Fluid pressure brake equipment



May 21, 1940- E. s. cooK El AL FLUID PRESSURE BRAKE EQUIPMENT 4 Sheets-Sheet 1 Filed June 10, 1938 mwozirro U Mm m ww r +0 E mm, mm womb? mvmwow 4 in m ww mm w I to? 92 m am 1 1 m o mmwum om+ 7 oo NEE 32mm 9v. o.

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FLUID PRESSURE BRAKE EQUIPMENT Filed June 10, 1939 4 Sheets-Shei 3 QUICK SERVICE CHAMBER CYLINDER' IOq H2 IIIHII IIIlml'lll INVENTORS I EARLE s. 00 0 K BY .JOHN CANETTA Patented May 21, 1940 UNITED STATES PATENT orricc' FLUID PRESSUREBRAKE EQUIPMENT.

and John ama-a; Wilkinsburg, Pa., The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Penn- Earle S. Cook assignors to sylvania Application June 10, 1938, Serial No. 212,873 In Chile and Argentina April 18, 1938 14 Claims.

This inventionrelates to fluid pressure brakes and more particularly to a brake equipment of the type having means for maintaining brake valve device, an auxiliary reservoir, a supplementary reservoir, and an-applica'tion control 'valve device, the control valve device being automatically operative in effecting an application of the brakes to admit fluid under pressure from the supplemental reservoir to the brake cylinder when, due to leakage, the brake cylinder pressure reduces. In such a brake equipment there is at all times a communication between the supplemental reservoir and the auxiliary reservoir so that when in maintaining brake cylinder pressure against leakage the pressure of the sup-' plemental reservoir is reduced below auxiliary reservoir pressure fluid under pressure will flow from the auxiliary reservoir to the supplemental reservoir and consequently to the brake cylinder. When due to thisflow of fluid the auxiliary reservoir pressure falls below brake pipe pressure the triple valve piston will move to release position in which theusual feed groove which extends from one side of the piston to the other will be opened and therefore permit fluid under pressure to flow from the brake pipe to the brake cylinder.

When the triple valve. piston and associated graduating and main valves thus move to release position the application control valve vdevice remains in application position so that the.

release of the brakes is not effected. To'effcct the release of the brakes it is necessary to increase brake pipe pressure. Since in maintaining brake cylinder pressure thebrake pipe and auxiliary reservoir have been reduced considerably below that normally required to effect an application of the brakes the rechargingof the brake pipe to effect release of thev brakes will be objectionably-delayed. Insome cases wherethe brake cylinder leakage on a long train is execssive the normal rate of increase in brake pipe pressure may be insufficient to eiiect the release of the brakes. From the foregoing it willbe understood that on long trains, say for instance sevently-five or more cars, the effect of brake cylinder leakage on the rate of increase in. brake pipe pressure will be such as to so delay the release of the brakes that the equipment will be devoid of its required flexibility of ,control.

On trains Where the cars are equipped with layed due-to the robbing of-Ybrake pipeand o auxiliary reservoir of fluid to maintain the brake... cylinder pressure against leakage. The principal object of the present invention is to provide an improved fluid pressure brake equipment of the above type which will be free 15 of the above mentioned objectionable. features.. Another object of the invention is to provide" an improved fluid pressure brake equipment of the above mentioned type having means whereby when an application of the brakes has been ef- 20 fected the brake cylinder pressure may be main,-. tained against leakage without increasing the' period of time normally required to efieot a release of the brakes. l

I .Another object ofthe invention is to provide 5 an improved fluid pressure brake equipment of the above mentioned type having means whereby when an application of the brakes has been effected the-brake cylinder pressure may be maintained against leakage without effecting. a re- 30 duction in auxiliary reservoir pressure or brake pipe pressure or both. v 7 Other objects and advantages will be apparent from the following more detailed description of the invention. I

In the accompanying drawings, Fig. l is a dia grammatic 'view, mainly in section, of a fluid pressure brake equipment embodying oneiorm of the invention; Fig. 2'is' a similar diagrammatic view of a fluid pressure brake equipment 40 embodying another form of the invention and Fig. 3 isa diagrammatic view, partly in section," of a fluid pressure brake equipment embodying still another form of the invention; and Figs. 4 and 5 are fragmentary diagrammatic sectional 45 views, each illustrating still another form of the, invention. 7 r As shown in Fig; 1 of the drawings the improved fluid pressure brake equipment may comprise a brake pipe I, a brake icontrolling valve 50 mechanism 2, an auxiliary reservoir 3, a reservev reservoir 4 and a brake cylinder-i5. Thebrake controlling valve mechanism 2 may comprise a pipe bracketli having formed therein a-control reservoir '1. Secured to one side of this pipe bracket by any suitable means is a triple valve device 8 and secured to the opposite side is an application control valve device 9.

The triple valve device may comprise a casing having formed therein a chamber I!) which is connected through a passage I I to the brake pipe I and which contains a piston I2having' a stem I3 for actuating a main slide valve I4 and a graduating valve I5 contained in a valve cham- Beyond the forward end'of the main slide valve I4 the outer end of the rod carrying the-graduating valve is operatively connected with the piston stem I3 by means of a pin 2I or the like which is rigidly secured to the stem in any desired manner.

The application control valve device 9 may comprise a casing having mounted therein a flexible diaphragm 22 to the opposite side of which is clamped inner andouter followers 23 and 24,

respectively. The inner follower 23 is provided with a-stem 25 for actuating a slide valve 26 contained in a chamber 2'! which is connected to the passage I1 and consequently to the auxiliary reservoir and slide valve chamber I B of the triple valve device. 1

The follower stem 25 for the greater portion of its length is hollow and has slidably mounted therein a plunger 28. The inner end of this plunger is normally maintained out of engage- "ment with the follower 23 by'means of aspring 29, and the inner end is engaged by one end of a plunger extension 3|! which extends through a central opening in a member 3I secured to the -casing and forming a wall of the chamber 21; said plunger extension being provided with labyrinth packing means to prevent the escapeof fluid under pressurefromthe chamber 21 to the opposite side of the wall member 3I.

At the outer side of the flexiblediaphragm. 22

'and containing the outer follower 24 is achamber I 32 which is connected to the control reservoir I through a passage 33 and a branch passage 34,

the passage 33 leading to the seat for the control slide valve 26. v

The application control'valve device may also comprise a flexible diaphragm 35 which is mounted in the casing and is located beyond the wall member 3|, the chamber defined by the casing member 3| and one sideof the diaphragm being connected to the atmospherethrough apassage 36. At the other side of the diaphragm. 35 is a chamber 31 to which the brake cylinder 5 is connected through a pipe and passage 38 and passages 39 and 40. The passage 39 leads at one end to the seat for the triple valve main slide valve and at the other end leads to the seat for the control slide valve 26. Leading from the passage 40 to theseat for the control slide valve 26 is a branch passage 4|.

Contained in the chamber 31 and-interposed between and engaging a spring seat-associated with the casing and a follower- 42 -which is clamped to the diaphragm 35 is a spring 43. The

follower 42 operatively engages the adjacent end of the plunger extension 30.

The reserve reservoir 4 is connected through a passage and pipe 5| to a passage 50 which leads at one end to the seat for the triple valve main slide valve and at the other end to the seat for the control slide valve 26.

Initial charging of equipment In initially charging the equipment fluid under pressure is supplied to the brake pipe I and triple valve piston chamber ID in the usual manner as-- suming the several parts of the triple valve device and application control valve device to be in release position as shown in Fig. 1, fluid under pressure flows from the triple valve piston cham-- her I?) through a feed passage 46 to the triple valve slide valve chamber I6, and from thence flows through passage I1 and passage and pipe I 8 to the auxiliary reservoir 3 Fluid under pres surealso flows from the passage I7 to the. slide valve chamber 21 of the application control valve device.

From the chamber 21 fluid under pressure flows;a

through a small port 41 in the control slide valve 26 and passage 33 to the control reservoir I. and from the passage 33 flows through branch passage 34 to the diaphragm. chamber 32 of the application control valve device.

Fluid under pressure supplied to the valve chamber E5 of the triple valve device, besides flowing to the auxiliary reservoir 3 as hereinbefore described, also flows to the reserve reservoir 4 by way of a restricted passage 48, a cavity 49 in the triple valve main slide valve, passage 50 and branch passage and pipe 5|, the passage 5|] leading to the seat for the control slide valve 26.

With the equipment fullycharged with fluid under pressure and the several parts of the brake controlling valve mechanism in release position" the brake cylinder 5 is connected to the atmosphere through pipe and passage 38, passage 39, a cavity 52 in the control slide valve 26,-a passage 53, a cavity 54 in the triple valve main slide valve and a passage 55, so that the brakes will" be released. The chamber 31 of the application control valve, since it is in open communication with the passage 39 by way of passage 40, will be at atmospheric pressure.

Since with the equipment fully charged the pressures of fluid acting on opposite sides of the flexible diaphragm 22 are substantially equal to each other, the several parts of theapplication control valve device will remain in release position.

Application of the brakes To efiect an application of the brakes a reduction in brake pipe pressure is effected in the usual manner. This reduction is effective in the piston chamber I5, so that fluid at the higher auxiliary 6 reservoir pressure in valve chamber I6 causes the piston I2 of the triple valve deviceand thereby the associated main and graduating valve to move to application position, the piston in its application position sealing against a gasket 56 which valve I5 relative to the main slide valve I4 to establish communication from the valve chamber It to the service port 20 in the main slide valve. Following the closing of the. feed passage,a lug 58 on the inner end of the "triple valve piston stem I3 engages the rear end of the main slide valve and, as the piston continues to move,shifts both valves in unison toward application position. The main slide valve as it is initially moved cuts ofi communication from the passage 53 to the passage 55 leading to the atmosphere, and at substantially the same time cuts off communication between the passages 48 and 50' thereby isolating the auxiliary reservoir from the reserve reservoir 4. Now when the main slide valve moves into application position, the service port 20, which has been previously opened by the graduating valve l5, registers with the passage 39, so that fluid under pressure flows from the triple valve slide valve chamber H3 and consequently 'from the auxiliary reservoir to both the brake cylinder 5 and chamber 31 of the application control valve device, Fluid under pressure thus supplied causes the brake cylinder to operate to initiate an application of the brakes.

' Since the valve chamber 21 of the application control valve device is in open communication 5 with the auxiliary reservoir 3, the pressure of fluid in this chamber reduces with auxiliary reservoir pressure. Upon the reduction in the chamber pressure the pressure of fluid in the control chamber 32 causes the diaphragm 22 to flex inwardly thereby causing the followers 23 and 24 and slide valve 26 to move in the same direction. As the slide valve 26 is thus being moved it first laps the passage 33, thereby cutting off communication between the valve chamber 21 and the control reservoir 1. After the passage 33 is lapped the continued inward movement of the diaphragm causes the follower 23 to engage the end of the plunger 28 and through the medium of this plunger, the plunger extension 30 and follower 42, flexes the diaphragm 35 outwardly against the opposing pressures of the spring 43 and the rising brake cylinder pressure in chamber 31. The follower as it continues to move shifts the control slide valve to application position in which a cavity 51 in the valve connects the brake cylinder branch passage 4| to the passage 50, so that fluid under pressure now flows from the reserve reservoir 4 to the brake cylinder 5 by way of pipe and passage 5|, passage 5|], cavity 57, branch passage 4|, passage 40, passage 39 and passage and pipe 38. Fluid under pressure supplied to the passage 40 also flows to the diaphragm chamber 31.

The slide valve 26 in application position laps the brake cylinder passage 39.

Now when the brake pipe reduction is stopped by turning the usual brake valve device (not shown) to lap position and the pressure of fluid in the triple valve slide valve chamber 5 and below brake pipe pressure in the triple valve chamber is in open communication with the auxiliary reservoir. Now when the brake cylinder pressure present in chamber 31 is increased by the continued flow of fluid from the reserve reservoir to overcome the pressure of fluid in the control chamber 32 and acting on the diaphragm 22, the diaphragm 35 acts to shift the follower and thereby the slide valve 26 toward release position until the valve cuts oil communication between the passages 55 and 4|. This cuts ofl the flow of fluid from the reserve reservoir tothe brake cylinder and chamber 3'! and since the ,8 pressure in the chamber can not now increase the several parts of the control valve device will come to a stop so that the brakes will be held applied.

Maintaining brake cylinder pressure against leak-Q.

. age

device and application control valve device are in, 15

lap position, the pressure of fluid in the chamber 3? of the application control valve device will reduce with brake cylinder pressure and the pressure of fluid in the control chamber 32 will as a consequence cause the diaphragm 22 to flex in-,,. wardly thereby moving the slide valve 26 from lap position to application position inwhich fluid under pressure again flows from the reserve reservoir 4 to the brake cylinder in the same manner as above described in connection with the application of the brakes until such time as the brake cylinder pressure present in chamber 3'! becomes suflicient to cause the return of the several parts of the application control valve device to application lap position, It will thus be seen that, brake cylinder pressure is maintained against? leakage by fluid under pressure supplied from only the reserve reservoir 4, the auxiliary reservoir being isolated from the reserve reservoir with the triple valve device in application lap position and the application control valve device in either application position orapplication lap position.

Since, in maintaining the brake cylinder pressure against leakage, the auxiliary reservoir pressure cannot be reduced, the triple valve device! will remain in application lap position, so that the feed passage 46 will remain closed to the brake pipe, therefore there can be no flow of fluid under pressurefrom the brake pipe to the brake cylin der when leakage from the brake cylinder occurs? From the above description it will be apparent that the maintenance of brake cylinder pressure against leakage will in no way reduce auxiliary reservoir or brake pipe pressure and therefore cannot increase the time required to effect a release of the brakes.

Full release of the brakes Assuming the several parts of the triple valve device and application control valve device to be in application lap position and it is desired to effect the release of the brakes, the pressure of fluid in the brake pipe is increased in the usual manner. This increase in brake pipe pressure causes the piston I2 and thereby the main valve l4 and graduating valve to move inwardly to release position in which the piston uncovers the feed passage 46 to the triple valve piston chamber ID, the cavity 45 in the main slidevalve |4 connects the passages 50 and 48 together and the cavity 54 also in the main slide valve connects the passage 53 to the exhaust passage 55.

With the feed passage 46 thus connected to the piston chamber I9 fluid under pressure flows 7o' through this passage tothe triple valve slide" valve chamber l6 and from thence flows to the auxiliary reservoir 3 and chamber 21 of the application control valve device byway of passage I1. I I 75 The increase in the pressure of fluid in chamber 21 due to the flow of fluid under pressure from under pressureis now vented from the brake cylinder and chamber 3'! of the application control valve device by way of passage 39, cavity 52,

. passage 53, cavity 54 in the main slide valve of the triple valve device and exhaust passage 55.

With the passages 48 and 55 connected together by means of the cavity 49 in the main slide valve of the triple valve device the reserve reservoir is recharged with fluid under pressure from the triple valve slide valve chamber I 6. With the slide valve 25 of the application control valve device in release position the port 4'! in the valve is open to the passage 33 so that if the control reservoir pressure has for any reason reduced during an application of the brakes it fr'nay be restored by the flow of fluid through this port and passage.

Graduated release of the brakes When it is desired to graduate the release of the brakes, that is to say, release the brakes in steps or increments the brake pipe pressure is increased in any desired number of steps, the

amount of increase in brake pipe pressure for each step being dependent upon the manipulation of the usual brake valve device by the engineman. When a step increase in brake pipe pressure is efiected, the triple valve device and application control valve device will operate in the same manner as hereinbefore described in connection with the full release of the brakes to release fluid under pressure from the brake cylinder and consequently from the chamber 3'! of the application control valve device. Upon the reduction in the pressure of fluid in chamber 31 the pressure of fluid in diaphragm chamber 32 causes the diaphragm 22 to flex inwardly thereby moving the slide valve 26 in the same direction to lap the passage 39. With the passage 39 thus lapped the further flow of fluid from the brake cylinder to the atmosphere is cut off and as a consequence the several parts of the application control valve device come to an immediate stop in release lap position. Upon a further step increase in brake pipe pressure the several parts of the application control valve device will be caused to move outwardly again to release position and when the reduction in brake cylinder pressure as called for by the amount of increase in brake pipe pressure has been effected the parts of the device are caused to again move to release lap position. From this it will be seen that the brakes may be released in a plurality of steps.

It will here be noted that if, during an application of the brakes, the brake cylinder pressure has been maintained against leakage, the rate of the subsequent release of the brakes whether it be a straight away release or a graduated release will not be slowed up since the maintenance of brake cylinder pressure can in no way reduce brake pipe pressure or auxiliary reservoir pressure. From this it is obvious that the present invention insures the obtaining of the necessary quick release of the brakes.

pipe bracket.

Description of equipment shoum in Fig. 2

In Fig. 2 another form of the invention is shown in which the several parts of the brake equipment with but several exceptions may be the equipment illustrated in Fig. 1 in that it includes an inshot valve device 15, a passage 16 connecting the reserve reservoir 4 to the feed passage 46 of the triple valve device. Another 1 difference resides in the elimination of the control of the passage 50 by the operation of the application control valve device and the addition 7 of means to the triplevalve device for such controh;

the elimination of the cavity 49 from the triple valve main slide valve and the elimination of the charging passage 48 leading from the triple valve slide valve chamber S6. A further difference resides in the provision of a passage T! which leads from the seat for the slide valve 26 of the appli-" cation control valve device to the inshot valve device for the purpose of controlling the flow of fluid from the reserve reservoir G as will hereinafter more'fully appear. Other differences will be obvious from the following detailed description of the inshot valve device, and the operation of the equipment.

The inshot valve device '15 may comprise a piston assemblage consisting of spaced but con nected pistons 18 and E9, the piston 78 being of greater diameter than piston 19. The face of the piston E9 is exposed to a valve chamber 80 which contains an inshot control valve 8! adapted to be actuated by the piston assemblage to control communication between the valve chain-" her and a passage l4 leading from the seat for the triple valve main slide valve. The chamber 88 is connected to a passage 82 leading from the seat for the triple valve main slide valve and is also connected to the brake cylinder passage 39. 4 The face of the piston i8 is exposed to a chamber 83 which is connected by way of a passage 84 to the passage 82. Between the pistons 18 and 19 there is a chamber 85 which is in open communication with the atmosphere through ai passage 86. The valve 8| is biased in a direction away from its seat by a light spring 81.

As will hereinafter more fully appear the inshot valve device functions to isolate the reserve reservoir 4 from the auxiliary reservoir 3 when an application of the brakes is being effected.

Initial charging of the equipment shown in Fig. 2

With the several parts of the equipment inW; release position as shown, fluid under pressure supplied to the brake pipe and triple valve piston chamber i0 flows through feed passage 46 to the triple valve slide valve chamber l6 and from thence flows through passage l'l directly to the c chamber 2? of the application control valve device and to passage and pipe l8 and from thence to the auxiliary reservoir 3. From the chamber 2'! fluid under pressure flows through the port 4'! in the control slide valve 26 and the register ing passage 33 to the control reservoir 1 in the Fluid under pressure flows from passage'33 through passage 34 to the control diaphragm chamber 32 From the feed passage 46 fluid under pressure from the'reserve'res'ervoir 4 to the brake cylinder' flows through passage 16, passage 50 and passage and pipe 5| to the reserve reservoir 4, there being a check valve 88 interposed in passage 16 adapted to prevent back flow of fluid under pressure from the reserve reservoir to the feed passage.

The brake cylinder is connected to the atmosphere by way of pipe and passage 38, passage 39, cavity 52 in the control slide valve 26, passage 53, cavity 54 in the triple valve main slide valve and passage 55. The chamber 31 of the application control valve device, since it is connected through passage 40 to the passage 39, is at atmospheric pressure as are the chambers 8|] and 83 of the inshot valve device 15 which are in open communication with the passage 39.

Application of the Makes-Fig. 2

When the brake pipe is reduced to effect an application of the brakes the several parts of the triple valve device are shifted in the same manner as hereinbefore described in connection with the equipment shown in Fig. 1 to first close the feed passage 46, out off the exhaust communication from the brake cylinder to the atmosphere 1 by way of passage 55 and establish communica- :gasket 56, the service port 20, which has been previously opened by movement of the graduating valve l5 relative to the main-valve, registers with passage 82 so that fluid under pressurenow flows from the auxiliary reservoir to the brake cylinder by way of pipe and passage l8, passage [1, triple valve slide valve chamber l6, service port 20, passage 82, chamber 80, passage 39 and passage and pipe 38.

Further with the triple valve parts in application position a cavity 89 in thetriple valve main slide valve connects the passage 50 to the passage 14 and since the reserve reservoir 4 is con-v nected through pipe and passage 5| to passage 59, fluid under pressure flows from the reserve reservoir to the brake cylinder by way of passage 14, past the unseated inshot control valve 8|, inshot valve chamber 80 and passage 39.

It will be seen that when the triple valve main slide valve is in application position an inshot of fluid under pressure is admitted to the brake cylinder from both the auxiliary reservoir and reserve reservoir which inshot acts to cause the brake cylinder to operate quickly to move the brake shoes of the usual brake rigging (not shown), into contact with the vehicle wheels. Fluid under pressure flows from the passage 82 through passage 84 to the piston chamber 83 of the inshot valve device and causes the inshot piston assembly to move inwardly, thereby actuating the inshot valve 8| to cut oil the flow of reserve reservoir fluid to the valve chamber 80, the inshot valve having no control whatever over the flow of fluid from the auxiliary reservoir.

When, due to the flow of fluid from the auxiliary reservoir, to the brake cylinder, the pressure of fluid in chamber 2'! of theapplication control valve device reduces, the pressure of fluid in the control chamber 32 causes the several parts of the device to move to application position. In application position a cavity 99 in the control slide valve connects the passage 1! to the brake cylinder branch passage 4!. The passage I1 is connected to the passage i l at a point located intermediate the triple valve main slide valve and the inshot valve 8|, so that fluid under pressure now flows by way of pipe and passage 5|, passages 50, cavity 89 in the triple valve main slide valve passage 14, passage Tl, cavity 90 in the control slide Valve, passages 4|, 4U, 39 and passage and pipe 38.

When the brake application as called for by the amount of reduction in brake pipe pressure has been effected the triple valve device and application control valve device will both assume application lap position in the same manner as has been previously described in connection with the operation of the equipment shown in Fig. 1, the triple valve device in this position maintaining the service port 20 so that there can be no flow of fluid from the auxiliary reservoir to the brake cylinder and the application control valve device maintaining the passage 11 closed and disconnected from the brake cylinder-branch passage 4| so that there can be no flow of fluid from the reserve reservoir to the brake cylinder.

If there should be leakage from the brake cylinder this leakagewill effect a reduction in the pressure of fluid in chamber 31 of the application control valve device. When this occurs the higher pressure in diaphragm chamber 32 causes the several parts of thedevice to again assume application position in which the cavity 98 in the control slide valve 26 connects the passages TI and 4| thus admitting fluid under pressure from the reserve reservoir 4 to the brake cylinder to compensate for such leakage. It will thus be seen that since the triple valve device is in application lap position there can be no flow from the auxiliary reservoir to the brake cylinder to compensate for brake cylinder leakage. In this connection it will be understood that the check valve 88 will not be unseated to permit flow of fluid from the auxiliary reservoir so long as the reserve reservoir pressure does not fall below auxiliary reservoir pressure.

If brake cylinder leakage should be such that the reserve reservoir pressure falls below auxiliary reservoir pressure fluid under pressure will flow from the auxiliary reservoir by way of the feed passage 45, check valve 88, passage 16, passage 59, cavity 89 in the triple valve main slide valve, passage 14, passage TI, cavity 90 in the control slide valve 25, passages 4|, 4|], 39 and passage and pipe 38. When the auxiliary reservoirpressure is thus reduced, fluid at brake pipe pressure in triple valve piston chamber will cause the triple valve piston l2 and thereby the associated valves 4 and 5 to move to release position. The triple valve main slide valve in this position laps the passage 14 thereby cutting ofiall flow of fluid to the brake cylinder, thus preventing a fur,-

ther reduction in auxiliary reservoir pressure and further preventing the loss of brake pipe fluid wh'ichwould otherwise occur by way of the feed passage 46 which has been uncovered to the chamber It by the piston l2.

Release of'the brakes-Fig. 2

The full or graduated release of the brakes is accomplished in substantially the same manner as before described in connection with the equippressure has been reduced to a very low value, say 75V for instance to three pounds, the'light coil spring acts to unseat the inshot valve 8| thereby moving the piston assemblage to its normal release position in which it is shown in Fig. 2.

mentshown in Fig. 2.

in Fig. 3 differs from that shown in Fig. 2 in the Description of equipment shown in Fig. 3

omission of the reserve reservoir charging, pas

sage iii andcheck valve'fisunterposed thereirr'andalso in the oniission'of the control passage 11, and

;in'"COlllllllllil1g thepassage' 50to the seat for the controlslide valve 16. Another difference resides in the provision of quick service means which is associated with the triple valve device and which is' adapted to effect a limited local reduction in brake pipe pressure when an application of the brakes is being effected. A further difference resides in the provision of a valve device I which is adapted to be controlled by brake cylinder pressure for isolating the reserve reservoir 4 from the auxiliary reservoir 3 when an application of the brakes is being effected and for establishing a charging communication from the auxiliary reservoir to the reserve reservoir when the brakes are being released.

Since the valve device I00 is the only new part included in the equipment and the other parts of the equipment have heretofore been described in detail in connection with Figs. 1 and 2, the following detailed description will be limited to the device and its association with the other parts of the equipment.

The valve device I 00 may comprise a casing having operatively mounted therein a piston IUI which is provided with a stem I02 adapted to actuate a slide valve I03 contained in a chamber I04 which is in communication with the atmosphere by way of a passage I05. At the face side of the piston IOI there is a chamber I06 which is connected through a branch passage and pipe I0! to the brake cylinder pipe 38. Contained in chamber IM is a spring I08 which is interposed between and operatively engages the inner end of the piston stem I02 and the casing. This spring acts to normally maintain the piston in its brake releasing position as shown in Fig 3 and thereby der pressure supplied to the brake pipe I flows through passage II to the triple valve piston chamber It and from thence flows through feed passage 65 to the valve chamber I6. From this chamber fluid under pressure flows through passage Il and passage and pipe I8 to the auxiliary reservoir 3.

The pipe i8 is provided with a branch pipe and passage Hi9 which leads to the seat for the slide valve I03 of the valve device I00 where, with the slide valve in its normal position as shown, a cavity Ihl in the slide valve connects the passage IIlQ to a passage and pipe III connected to the reserve reservoir pipe I. From this it is apparent that fluid under pressure flows from the pipe is to the reserve reservoir. To prevent the flow of fluid from the pipe I8 to the reserve reservoir from unduly slowing up the rate of charge of the auxiliary reservoir the rate of charge of the reserve reservoir is retarded by means of a choke IIZ which is interposed in the passage I09 as shown or if desired this choke may be'interposed in the passage I I I.

Aside from the charging of the auxiliary reservoir 3 and reserve reservoir-4 in the manner just described the equipment will be charged with fluid under pressure in the same manner as has heretofore been: described in connection with Fig: 2.,

Application of the brakesFig. 3

Vlflien the-brakepipe pressure has been reducedto eflect anapplication oi the brakes the tripl'e*va1ve-= device moves to application position inwliich fluid under pressure is supplied from both theauxiliary reservoir and the reserve reservoir to the brake cylinder, the flow of fluid fromthe reserve reservoir being by way of the inshot valve 8i as described. When the brake cylinder pressure has been increased to a predetermined degree the inshot valve device operates to cut off the flow of fluid from the reserve reservoir to the brake cylinder by way of the inshot valve chamber 80 in the same manner as has been fully set forth in connection with the equipment illustrated in Fig. 2.

Fluid under pressure being supplied to the brake cylinder flows by way of branch passage Ill! to the piston chamber I06 of the valve device I00, causing the piston to move and shift the slide valve I03 to lap passage III. With the slide valve in this position the auxiliary reservoir and reserve reservoir are isolated from each other. i

In response to the reduction in auxiliary reservoir pressure effected by the flow of fluid to the brake cylinder the several parts of the application control valve device move inwardly to application position as described in connection with the equipment shown in Fig. 2.

In application position the cavity 90 in the slide valve 28 connects the passage 50 to the brake cylinder branch passage II, so that even though the inshot valve 8| is closed fluid under pressure will flow at a slower rate from the reserve res-ervoir to the brake cylinder by way of pipe and passage 52, passage 50, cavity 90 in the control slide valve 26, passages 4|, 40 and 39 and passage and pipe 38.

Now when the triple valve device and application control valve device assume application lap position in the manner described in connection with the equipment illustrated in either Fig. l or Fig. 2, the graduating valve I 5 outs ofi the flow of fluid from the auxiliary reservoir to the brake cylinder and the control slide valve 26 cuts off the flow of fluid from the reserve reservoir 4 to the brake cylinder.

When the triple valve main slide valve I4 moves to application position a cavity I I3 therein connects a passage H4 leading from the triple valve piston chamber I0 and thereby from the brake pipe to a passage II5 leading to a quick service chamber H8, so that fluid under pressure is locally vented from the brake pipe.

If leakage occurs from the brake cylinder the brake cylinder pressure and consequently the pressure of chamber 31 of the application control valve device which is in open communication with the brake cylinder will be correspondingly reduced. Upon such reduction the pressure of fluid in control chamber 32 causes the several parts of the application' control valve device to again assume application position in which fluid under pressure flows from the reserve reservoir to the brake cylinder until such time as the supply of fluid from the reserve reservoir to the brake cylinder compensates for such leakage. When this is accomplished the several parts of the device are caused to again assume application lap position. These maintaining operations may continue until the pressures of the reserve reservoir are equalized. The reserve reservoir is made of sufficiently large volume to maintain brake cylinder pressure against leakage under ordinary conditions of service. This is also true as to all of the other forms of the invention shown in the drawings. It will here be understood that since brake cylinder leakage cannot reduce auxiliary reservoir pressure the triple valve device will remain in application lap position during the maintaining operations of the application control valve device.

Since as just described the maintenance of brake cylinder pressure against leakage cannot rob the auxiliary reservoir and therefore the brake pipe of fluid under pressure it follows that this feature can in no way adversely affect the prompt release of the brakes.

Release of the brakes-Fig. 3

In releasing the brakes the triple valve device and application control valve device are caused to move to release position in substantially the same manner as previously described in con nection with the equipment shown in either Fig. 1 or Fig. 2. In the present equipment however the recharge of the reserve reservoir is accomplished in a difierent manner than in the equipments of Figs. 1 and 2. In the present equipment when, in releasing the brakes, the brake cylinder pressure has been reduced to some very low degree the spring I08, of the valve device I 00 acts to return the piston I BI and thereby the slide valve I03 to normal release position in which the cavity I III in the valve again connects the passages I09 and III and permits fluid under pressure to flow from the auxiliary reservoir pipe I8 to the reserve reservoir 4.

With the main slide valve of the triple valve device in release position the cavity II3 connects the passage M5 to the passage 14 so that when the inshot valve SI is caused to move from its seat, fluid under pressure is vented from the quick service chamber with fluid being vented from the brake cylinder by way of passage 39.

In graduating the release of the brakes the valve device I00 in no way alters the graduating operations of the application control valve device.

' Description of the equipment shown in Fig. 4

In Fig. 4 another form of the invention is illustrated in which the valve device for isolating the auxiliary reservoir 3-and reserve reservoir from each other in effecting an application of the brakes and for establishing the charging communication from the auxiliary reservoir to the reserve reservoir in effecting the release of the brakes, maybe identical in construction with I that of the corresponding valve device I00 of the equipment shown in Fig. 3 or may be constructed according to the showing in Fig. 4.

If the valve device I00 as shown in Fig. 3 is employed the piston chamber I00 is connected to the quick service chamber III so that when slide valve I03 to close the communication between the auxiliary reservoir and reserve reservoir. When in releasing the brakes the quick service chamber and thereby the piston chamber I06 of the valve device is vented to the atmosphere, the spring I08 of the device acts to shift the piston IOI and thereby the slide valve I03 to their normal position as shown in Fig. 3 in which position the cavity III] in the slide valve again establishes the charging communication between the auxiliary reservoir 3 and reserve reservoir 4.

The construction of the valve device shown in Fig. 4 differs somewhat from that of the corresponding device shown in Fig, 3 and will therefore be referred to as the valve device I50.

This valve device I50 may comprise a casing in which there is operativelymounted a piston I5I having a stem I52 adapted to actuate a slide valve I53 contained in a chamber I54 which is constantly connected to the auxiliary reservoir passage I09 by way of a passage I55. At the face side of the piston I5I there is a chamber I56 which is connected through a pipe and passage I51 to the quick service chamber H6. Interposed between and operatively engaging the casing and the face of the piston is a spring I58 which at all times tends to move the piston inwardly from the position in which it is shown; Since as previouslydescribed the quick service.

chamber is normally at atmospheric pressure, the piston chamber I56 of the valve device I50 will also be at atmospheric pressure, so that when the equipment is' charged with fluid under pressure the piston I5I and thereby the slide valve I53 will be maintained in their normal position against the opposing pressure of the spring I 58 by the pressure of fiuid'in valve chamber I54 as supplied from the auxiliary reservoir through the passages I09 and*I55. In this position a cavity I59 connects the passages I09 and III together so that the reserve reservoir is charged with fluid under pressure by way of the auxiliary reservoir 3 in the same manner as described in connection with the equipment shown in Fig. 3.

When an application of the brakes is being effected the falling auxiliary reservoir pressure in valve chamber I54 and the-rising quick service chamber pressure in piston chamber I56 become substantially equal, the spring I58 acts to shift the piston I5I and thereby the slide valve I53 inwardly a sufiicient distance to lap the passage I I I, thus closing the communication between the auxiliary reservoir and the reserve reservoir.

When, in releasing the brakes,'the rising auxiliary reservoir pressure in valve chamber I54 acting on the valve side of the piston I5I is sufficient to overcome the opposing pressures of the spring I 58 and the falling quick service chamber pressure acting on the face of the piston, the piston and thereby the slide valve I54 are again shifted to their normal positions as shown in Fig. 4. With the slide valve inthis position the cavity I59 again establishes communication between the auxiliary reservoir Ban-d the reserve reservoir 4.

Description of the equipment shown in Fig. 5

In Fig. 5 another form of the invention is illustrated which differs slightly from the equipments shown in Figs. 3 and 4. Instead of controlling the valve device which isolates the auxiliary reservoir and reserve reservoir when an application of the brakes is being effected by brake cylinder fluid as vshown in Fig.3 or by quick service reservoir fluid as shown in Fig. 4 the corresponding valve device H0 in Fig, 5 is adapted to actuate a slide valve 13 contained in a chen ber I14 which is in constant open communication with the auxiliary reservoir 3 by way of auxiliary reservoirpassage I69 and a branch auxiliary reservoir passage I15. At the face side of the piston I 'I.I there is a piston chamber I16 slide'valve chamber I6.

whichfasfshownfis normally connected through a pipe' passage I11Qand a port I18 in the tripleval've mainslide valvato' the triple valve Contained in the piston chamber ll'liis a spring I19 which at all times tendls to move the piston I1I inwardly.

With'the equipment fully charged both sides of the piston IE6 are subjected to auxiliary reservoir pressure, so that the spring I19 maintains the piston and thereby the slide valve I13 in their normal position as shown. With the slide valve I4 in this position a cavity I80 in the valve connects the passages I II and I09 together, thus establishing communication between the auxiliary reservoir 3 and the reserve reservoir 4.

When an application of the brakes is initiated by a reduction in brake pipe pressure and the triple valve parts move toward application position in response to the brake pipe reduction,

'the slide valve I4 in its movement shifts the port I18 out of registration with the passage I11 thus closing communication between the valve chamher It and the piston chamber I16. Immediate- ,ly following the closing of this communication M a cavity IBI in the main slide valve I4 connects i in its outer position laps the auxiliary reservoir passage I09 thus closing communication between the auxiliary reservoir and the reserve reservoir and thereby isolating the reserve reservoir from theauxiliary reservoir and brake pipe.

When in releasing the brakes the triple valve main slide valve I4 is returned to release posi tion' the atmospheric communication from the piston chamber I16 is closed and the port I18 is in'registration with the passage I11 so that fluid under pressure is again supplied from the slide valve I6 of the triple valve device to the piston chamber I16. Now when the pressure of fluid in chamber I16 becomes substantially equal to the pressure of fluid in valve chamber I14 the spring I19 acts to move the piston HI and thereby the slide valve I13 to their normal position as shown in Fig. 5, in which position the cavity ISO in the valve again connects the passages IIlS and III, so that fluid under pressure is now free to flow from the auxiliary reservoir pipe I8 to the reserve reservoir.

General considerations It Will be apparent from the drawings and the foregoing description that since, in effecting an application of the brakes, each of the forms of the invention disclosed functions to separate the reserve reservoir from the auxiliary reservoir so that in maintaining brake cylinder pressure against leakage the auxiliary reservoir, under azom e service conditions to be expected, will not be called upon to compensate for such leakage. By reason of this the auxiliary reservoir and brake pipe, in releasing the brakes, will be recharged in a much shorter time than if the auxiliary rcservoir pressure had been reduced more than called for by the degree of reduction in'brake pipe pressure required to'eife'ct' a chosen 'applicationbf 'the brakesfTliis insures the prompt and positive release of thebrakes'regardless of thelengthpf thetrain.

While several illustrative embodiments of our invei'ition have beendescribed'iirdetail, it not our intention to limit its scope to these embodiments or otherwise than by the termsof the'ap pended claims.

Having now described our invention, what we claim as new and desire to secure by Letters Pat ent, is:

1. In a fluid pressure brake equipment, in comb-ination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir "normally in communication with each other'arl'd charged brakes and further comprising a valve device responsive 'to a reduction in auxiliary reservoir pressure occasioned by the flow of fluid to the brake cylinder for supplying fluid under pressure frorn'said other reservoir to the brake cylinder to assist in effecting the application of the brakes, said valve means and valve device being operative upon the attainment of brake cylinder pressure called for by the reduction in brake pipe pressure for isolating said reservoirs from each other and from the brake cylinder and said 'valve device being operative upon a subsequent reduction in brake cylinder pressure due to leakage for again supplying fluid from said other reservoir to the brake cylinder to compensate for the leakage.

2. In a fluid pressure brake equipment; incombination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and charged with fluid under pressure, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first supply fluid under pressure from said auxiliary reservoir to the brake cylinder to effect an application of the brakes and being then operative upon a" reduction in auxiliary reservoir pressure resulting from the flow of fluid from the auxiliary reservoir to the brake cylinder to supply fluid under pressure from said other reservoir to the brake cylinder to assist in effecting an application of the brakes, said mechanism being operative upon the attainment of the brake cylinder pressure called for by the reduction in brake pipe pressure to isolate said reservoirs from each other and the brake cylinder and being operative upon a subsequent reduction in brake cylinder pressure for again supplying fluid from said other reservoir to the brake cylinder while maintaining the auxiliary reservoir isolated from said other reservoir and brake cylinder.

3. In a fluid pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first cl the charging communication fromthe brake pipe to said reservoirs and to then supply fluid under pressure from both reservoirs to the brake cylinder to efiect an application of the brakes and being then operative to isolate said reservoirs from each other andfrom the brake cylinder, said mechanism being operative upon leakage of fluid pressure from the brake cylinder for again supplying fluid under pressure from said other reservoir to the brake cylinder while maintaining the auxiliary reservoir isolated from said other reservoir and brake cylinder.

4. In a fluid pressure brake equipment, in combination, a brake pipe, a brake'cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and with the brake pipe and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close communication from the brake pipe to the reservoirs, to then supply fluid under pressure from both reservoirs to the brake cylinder to effect an application of the brakes and being then operative to isolate said reservoirs from each other and from the brake cylinder, said mechanism being operative upon a subsequent reduction in brake cylinder pressure for again supplying fluid from said other reservoir to the brake cylinder.

5. In a fluid pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and with the brake pipe and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close communication from the brake pipe to the reservoirs, to then supply fluid under pressure from both reservoirs to the brake cylinder to effect an application of the brakes and being then operative to isolate said reservoirs from each other and from the brake cylinder, said mechanismbeing operative upon a subsequent reduction in brake cylinder pressure for again supplying fluid from said other reservoir to the brake cylinder and while maintaining the brake pipe isolated from both reservoirs.

6. In a fluid pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and charged with fluid under pressure, and brake controlling mechanism comprising valve means operative upon a reduction in brake pipe pressure to isolate the reservoirs from each other and to supply fluid under pressure from said auxiliary reservoir to the brake cylinder to effect an application of the brakes, further comprising a valve device responsive to a reduction in auxiliary reservoir pressure occasioned by the flow of fluid to the brake cylinder for supplying fluid under pressure from said other reservoir to the brake cylinder to assist in efiecting the application of the brakes, said valve means and valve device being operative upon the attainment of the brake cylinder pressure called for by the reduction in brake pipe pressure for isolating said reservoirs from each other and from the brake cylinder, said valve device being operative upon a subsequent reduction in brake cylinder pressure due to leakage for again supplying fluid from said other reservoir to the brake cylinder to compensate for the leakage, said valve means being operative upon an increase in brake pipe pressure following an application of the brakes to vent fluid under pressure from the brake cylinder to efiect a release of the brakes and to again establish communication between the reservoirs.

. 7. In a fluid pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and another reservoir normally in communication with each other and with the brake pipe and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close communication from the brake pipe to the reservoirs, to then supply fluid under pressure from both reservoirs to the brake cylinder to effect an application of the brakes and being then operative to isolate said reservoirs from each other and from the brake cylinder, said mechanism being operative upon .a subsequent reduction in brake cylinder pressure for. again supplying fluid from said other reservoir to the brake cylinder and while maintaining the brake pipe isolated from both reservoirs saidmechanism being operative upon an increase in brake pipe pressure following an application of the' brakes to vent fluid under pressure from the brake cylinder to effect a release of the brakes and to again establish communication between both res-. ervoirs and between the brake pipe and both reservoirs. V

8. In a fluid pressure brake equipment, in combination, a brake pipe, an auxiliary reservoir and a reserve reservoir normally in communication with each other and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close the charging communication from the brake pipe to said reservoirs and to then supply fluid under pressure from both of the reservoirs for effecting anapplication of the brakes, and operative upon an increase in the pressure of the brake applying fluid to the degree called for bythe reduction in brake pipe pressure for isolating the reservoirs from each other and for cutting off the flow 'of brake applying fluid from both of the reservoirs, said brake controlling mechanism being operative upon a reduction in the pressure of they brake applying fluid for again supplying brake applying fluid from the reserve reservoir while maintaining the auxiliary reservoir isolated from the reserve reservoir.

9. In a fluid pressure brake equipment, in com-1 bination, a brake pipe, an auxiliary reservoir and a reserve reservoir normally in communication with each other and charged with fluid under pressure, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close the communication from the brake pipe to said reservoirs and to then supply fluid under pressure from both of the reservoirs for effecting an application of the brakes, and operative upon an increase in the pressure of the brake applying fluid to the degree called for by the reduction in brake pipe pressure for isolating the reservoirs from each other and for cutting off the flow of brake applying fluid from both of the reservoirs, said brake controlling mechanism being operative upon a reduction in the pressure of the brake applying fluid for again supplying brake applying fluid from the reserve reservoir while preventing the flow of brake applying fluid from the auxiliary reservoir.

10. In a fluid pressure brake equipment, in combination, a brake pipe, an auxiliary reservoir and a reserve reservoir normally in communication with each other and charged with fluid under pressure from the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close the charging communication from the brake pipe to said res ervoirs and to then supply fluid under pressure from both of the reservoirs for effecting an application of the brakes, and operative upon an increase in the pressure of the brake applying fluid to the degree called for by the reduction in brake pipe pressure for isolating the reservoirs from each other and for cutting off the flow of brake applying fluid from both of the reservoirs, said brake controlling mechanism being operative upon a reduction in the pressure of the brake applying fluid for again supplying brake applying fluid from the reserve reservoir while preventing a further reduction in auxiliary reservoir.

11. In a fluid pressure brake equipment, in combination, a brake pipe, an auxiliary reservoir and a reserve reservoir normally in communication with each other and charged with fluid under pressurefrom the brake pipe, and brake controlling mechanism operative upon a reduction in brake pipe pressure to first close the charging communication from the brake pipe to said reservoirs and to then supply fluid under pressure from both of the reservoirs for eiiecting an application of the brakes, and operative upon an increase in the pressure of the brake applying fluid to the degree called for by the reduction in brake pipe pressure for isolating the reservoirs from each other and for cutting oi the flow of brake applying fluid from both of the reservoirs, said brake controlling mechanism being operative upon a reduction in the pressure of the brake applying fluid for again supplying brake applying fluid from the reserve reservoir while maintaining closed the communication through which brake applying fluid was previously supplied from the auxiliary reservoir.

12. In a fluid pressure brake equipment, in combination, a brake pipe, an auxiliary reservoir and a reserve reservoir normally charged with fluid under pressure from the brake pipe, a brake controlling mechanism operative upon a reduction in brake pipe pressure for first closing the charging communication from the brake pipe to said reservoirs and for then supplying fluid under pressure from both of said reservoirs to effect an application of the brakes, operative upon an increase in the pressure of the brake applying fluid to the degree called for by the reduction in brake pipe pressure for cutting off the supply of brake applying fluid from both of the reservoirs, and operative automatically upon a reduction in the brake applying fluid due to leakage for supplying fluid under pressure from the reserve reservoir to compensate for said leakage, and means maintaining said auxiliary reservoir isolated from the reserve reservoir while fluid under pressure is being supplied to compensate for leakage.

13. In a'fluicl pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and a reserve reservoir normally charged with fluid under pressure, a triple valve device normally establishing communications through which both reservoirs are charged with fluid under pressure from the brake pipe, said triple valve device being operative upon a reduction in brake pipe pressure to close said communications and to establish a communication through which fluid under pressure flows from the auxiliary reservoir to the brake cylinder, an application control valve device operated upon a reduction in auxiliary reservoir pressure to establish a communication through which fluid under pressure flows from the reserve reservoir to assist in effecting the application of the brakes, said triple valve device and said application control valve device being operative upon the attainment of the brake cylinder pressure called for by the amount of reduction in brake pipe pressure to out off the flow of fluid to the brake cylinder, said application control valve device being automatically operative when leakage of fluid from the brake cylinder occurs for supplying fluid under pressure from the reserve reservoir to the brake cylinder.

14. In a fluid pressure brake equipment, in combination, a brake pipe, a brake cylinder, an auxiliary reservoir and a reserve reservoir normally charged with fluid under pressure, a triple valve device normally establishing communications through which both reservoirs are charged with fluid under pressure from the brake pipe, said triple valve device being operative upon a reduction in brake pipe pressure to close said communications and to establish a communication through which fluid under pressure flows from the auxiliary reservoir to the brake cylinder, an application control valve device operated upon a reduction in auxiliary reservoir pressure to establish a communication through which fluid under pressure flows from the reserve reservoir to assist in effecting the application of the brakes, said triple valve device and said application control valve device being operative upon the attainment of the brake cylinder pressure called for by the amount of reduction in brake pipe pressure to cut ofi the flow of fluid to the brake cylinder, said triple valve device in operating to cut off the flow of fluid to the brake cylinder isolating the auxiliary reservoir from the reserve reservoir, and said application control valve device being automatically operative when brake cylinder pressure is reduced by leakage to admit fluid under pressure from the reserve reservoir to the brake cylinder.

EARLE S. COOK. JOHN CANETTA. 

